DIVISIONS OF THE ANIMAL KINGDOM. Ivii 



all quadrupeds there is a growth of down or wool under- 

 neath the hair, and more or less mixed with it. In warm 

 countries, this wool is little if at all developed ; but, in the 

 colder, it frequently becomes the principal covering of the 

 skin, forming, along with the hair, a thick fur. In the warm- 

 est regions, the domestic sheep produces scarcely any wool ; 

 in temperate countries he has a fleece properly so called ; 

 and in the coldest of all, his wool is mixed with long hair 

 which covers it externally. The wool, an imperfect conduc- 

 tor of heat, preserves the natural temperature of the body, 

 and thus protects the animal from cold, while the long hair 

 is fitted to throw off the water which falls upon the body in 

 rain or snow. But in the warm season the wool, which 

 would be incommodious, falls off, to be renewed before win- 

 ter, while the hair always remains. The Dog, too, has a 

 coat of wool, which he loses in countries of great heat, but 

 which, in colder countries, grows so as to form, along with 

 the hair, a thick fur, so that, in certain colcT countries, there 

 have been formed breeds of dogs to produce wool for cloth- 

 ing. The dogs of Europe conveyed to warm countries fre- 

 quently lose even their hair, and become as naked as ele- 

 phants, and in every country their fur is suited to the nature 

 of the climate. 



Similar to the effects of temperature is that of humidity, 

 the hair becoming longer and more oily in the moister coun- 

 tries. Even within the limits of our own Islands, the Ox of 

 the western coasts, exposed to the humid vapours of the At- 

 lantic, has longer hair than the Ox of the eastern districts. 

 Even the effect of continued exposure to winds and storms 

 may modify parts of the animal form. There are certain 

 breeds of gallinaceous fowls which are destitute of the rump 

 so called. Most of the common fowls of the Isle of Arran, 

 on the coast of Scotland, have this peculiarity. This little 

 island consists of high hills, on which scarcely a bush exists 

 to shelter the animals which inhabit it from the continued 

 gales of the Atlantic. The feathers of a long tail might in- 



